The present invention relates to a suspension system for a motor vehicle.
A suspension system having a swing member such as an arm or link for pivotally connecting a wheel to a body of a motor vehicle is used. An end of the swing member is pivoted on the body through an elastic member such as rubber bush. The spring constant of the elastic member is determined to meet requirements of reduction of vibration of the body and noises, and improvement of steerability.
Japanese Patent Laid Open No. 60-146707 discloses a suspension system in which a hollow elastic member is disposed on a pivot of a swing member and the chamber of the elastic member is filled with oil. The spring constant is controlled by changing the pressure of oil in the chamber. However, the elastic member such as a rubber bush becomes deteriorated with the time by high pressure oil. Further, it is difficult to properly control the spring constant by changing the pressure of oil.